Question

Two spheres have radii 6 and 15. Find the ratios of the areas and the volumes.

Answer 1

1st sphere has r1 = 6

=> Surface area S1 = 4 x pi x r1^2 = 4 x pi x 6^2 = 144pi

=> Volume V1 = (4/3) x pi x r1^3 = (4/3) x pi x 6^3 =288pi

2nd sphere has r1 = 15

=> Surface area S1 = 4 x pi x r1^2 = 4 x pi x 15^2 = 900pi

=> Volume V1 = (4/3) x pi x r1^3 = (4/3) x pi x 15^3 =4500pi

=> S1/S2 = 144pi/900pi = 0.16

=> V1/V2 = 288pi/4500pi = 0.064

Hope this helps!

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